1. Technical Field
The invention relates to the field of allocating a frequency spectrum to a plurality of radio networks. More particularly, the invention departs from the situation that a spectrum resource has previously been allocated to each radio network or to a group of radio networks and proposes a method and a system for dynamically re-allocating the frequency spectrum.
2. Technical Background
In recent years wireless communications expanded rapidly and the current development shows clear signs of accelerated future growth. However, future growth is limited by the fact that the total frequency spectrum that is made available for wireless communications cannot keep pace with the increasing demands. There have thus been various approaches like channel splitting or advanced speech and data coding to improve spectrum efficiency. Additionally, technical improvements enable wireless communications to advance into increasingly higher frequency regions. In spite of all these attempts, spectrum resources have become scarce.
Due to the steadily increasing spectrum demands spectrum allocation has become an important topic. Basically, spectrum allocation belongs to the category of problems that concern the distribution of a scarce resource to a set of individuals having different demand for the resource.
In the past several approaches like beauty contests and auctions have been employed in order to allocate a frequency spectrum to a certain number of competing spectrum applicants (e.g. operators) for usage by their radio networks (RNs).
A beauty contest is a spectrum allocation scheme which is generally based on the spectrum applicant's prospects of the spectrum usage over several years and also on the related interests of governments. The complex nature of such beauty contests requires a long-term allocation of the spectrum resources.
As an alternative to beauty contests many governments have made use of auctioning schemes. Such schemes involve the auctioning of a plurality of spectrum licenses for typical license periods ranging from ten to twenty years. The settlement price of such auctions reflects the expected earnings from the services provided in the licensed spectrum over the license period.
As has become apparent from the above, the currently practiced long-term spectrum allocation schemes are not appropriate for dynamic spectrum allocation. If for example technical developments necessitate short-term re-allocations of the frequency spectrum allocated by means of the spectrum allocation schemes discussed above, such re-allocations cannot be dynamically performed today.
There is, therefore, a need for a method and a system for dynamically re-allocating a frequency spectrum to a plurality of RNs, which is more flexible and can easily be adapted to the ever-changing demand for spectrum resources.